This could take a couple or even a few weeks for her to get totally over this, but should stop her from digressing and you may see small improvements each day.
You're doing what I was going to suggest as in the vitamins. Get some E though too. 400 (approx) I.U. a few times a day. Give her scrambled eggs or tuna too for the selenium.
She should be still on grower crumbles as she wouldn't be laying for a couple of months yet.
Have you checked for...